Page 104 - Direct To ConsumerFINAL3.25

Sources:
• Vingren, J. L., Kraemer, W. J., Ratamess, N. A., Anderson, J. M., Volek, J. S., & Maresh, C. M. (2010). Testosterone physiology in resistance exercise and training. Sports Medicine, 40(12), 1037-1053.
• Hackney, A. C. (2006). Stress and the neuroendocrine system: the role of exercise as a stressor and modifier of stress. Expert Review of Endocrinology & Metabolism, 1(6), 783-792.
Additional Sources:
• Crewther, B. T., Cook, C. J., Cardinale, M., Weatherby, R. P., & Lowe, T. (2011). Two emerging concepts for elite athletes: The short-term effects of testosterone and cortisol on the neuromuscular system and the dose-response training role of these endogenous hormones. Sports Medicine, 41(2), 103-123.
• Hayes, L. D., Bickerstaff, G. F., & Baker, J. S. (2010). Interactions of cortisol, testosterone, and resistance training: influence of circadian rhythms. Chronobiology International, 27(4), 675- 705.
Vitamin D - Added Test to Sports Fitness
Vitamin D is not a direct measure of sports fitness, but it plays a crucial role in various physiological processes that can impact an athlete's performance, recovery, and overall health. It is a fat-soluble vitamin that is mainly produced in the skin upon exposure to sunlight and can also be obtained through dietary sources.
Some of the ways vitamin D can impact sports fitness include:
1. Bone health: Vitamin D is essential for calcium absorption, promoting healthy bone growth and maintaining bone density. Adequate vitamin D levels can help reduce the risk of stress fractures and support overall musculoskeletal health in athletes.
2. Muscle function: Vitamin D may influence muscle strength and function. Research has shown that low vitamin D levels can be associated with reduced muscle strength, particularly in the lower limbs, which can negatively impact sports performance.
104